Navigation instrument ality



May 22, 1945.

A. R. MORLEY ET AL .NAVIGATION INSTRUMENTALITY Filed Feb. 11, 1944 2Shefcs-Shet 1 May 22, 1945.

A. R. MORLEY ET AL NAVIGATION INSTRUMENTALITY Filed Feb. 11, 1944 2Sheets-Sheet 2 1705627 6'. Afa /61!,

' north-south and south-north directions of rotation of the globe, iscomprised in a cylindro-conic roller 24, that is keyed on a horizontalshaft 25,

which has its ends journaled in bearings 26 slidably mounted in slotways21, formed longitudinally in the arms 2 I. Housed within the slotways 21are springs 28, which act, through the bearings 26 and the shaft 25, tonormally withhold the roller 24 from frictional driving contact withthesurface of the globe. Also mounted on the shaft 25, is a bevel gear29, which is adapted to Y be meshed with a bevel pinion 30, that iskeyed on the lower'end of a shaft 3I extending upwardly within. thecasing I5, through the division wall or partition I4, and outwardly ofthe flange I2, of the neck portion of the casing. The lower end of theshaft 3| is journaled in a bearing bracket 32 secured to the ring-frameand has its upper end provided with a knurled operating dial 33.

The mechanism for the east-west and the westeast directions of rotationof the globe I5, is comprised in anothercylindroconic roller 34, theaxis of which is disposed at right angles to that of the roller 24 andis constituted in a vertical shaft 35, that has its ends journaled inbearings 36, which are slidably mounted in slotways formed longitudinally in the arms 22, at one side of the ringframe. Here, too, theslotways house springs 28' (Figure 4) that are cooperative with thebearings 36, after the manner of the springs 28 with the bearings 26,for normally withholding the roller 34 out of contact with the surfaceof the globe I5. Mounted on the shaft 35, is a spur gear 31, which isadapted to be meshed with a pinion 38, keyed on the'lower end of a shaft39, that extends upwardly within the casing, after the manner of theshaft 3|. The lower end of the shaft 39, immediately above the pinin'38,is journaled in a bearing bracket 40, secured to the side wall of thecasing, while an intermediate portion is journaled in' a'bearing 4|,mounted in the division wall or partition I4, and a portion of its upperend in a bearing 42, similarly mounted in the flange I2. The free end ofthis shaft 39 is also provided witha knurled operating dial 43.

The rollers 24, 34, are released from contact with the surface of theglobe I whenever the pinions 30, 38, are moved out of meshing engagementwiththe gears 29, 31, and they will effectively lock the globe in a setposition, whenever both pinions are meshed therewith at the same time.In order to move the pinions 30, 38 into and out of engagement with thegears 29, 31, the shafts 3|, 39, are each adapted for manipulationto'that end from the operating dials 33, 43, respectively. As best shownin Figure 3, the shaft 39 is arranged for vertical movement, within thelimits imposed by a pair of collars 44 keyed thereon, one immediatelyabove the bearing II and the other slightly spaced below the bearing 42,and is elevated to lift the pinion 38 from its meshing engagement withthe gear 31 by an upward pull on the dial 43. Upon release of the'dial43, the pinion 38 will be withheld from such engagement by the pressureof a spring 44 onthe upperof the collars 44, until the dial 43 is againdepressed, the spring 44 being supported on the side wall of the casingIt. The shaft 3I will be similarly arranged and equipped for themovement of the pinion 38 into and out of mesh with the gear 29,following each setting of the globe I5 with reference to the aperture 23in the division wall or partition I4.

For obtaining the stated directional movements of the globe l5, and asillustrated, the roller 24 is mounted horizontally at the front centralside of the globe, and the roller 34 vertically at the left central sidethereof, and by a proper manipulation of the dials 33, 43, any givenarea of the earths surface, as depicted on the surface of the globe maybe placed in registry with the aperture 23 in the center of the divisionwall or partition 14, for projection therethrough. In order toaccomplish this projection, a circular battery of electric lamps 45 ismounted on the lower side of the division wall or partition 14 aboutthe,

aperture 23, and they are housed within an annular reflector 45 designedto concentrate the light on that portion of the globe that is visiblethrough the aperture for its unobstructed reflection from the surface ofthe globe upwardly through the aperture, and, for present purposes,theaperture 23 will be circular and have'a diameter of one (1) inch, sothat the circular'area of the globe that is visible therethrough will beof approximately the'same diameter.

To project a chart-image of a selected area of the globe I5 brought intoregistry withthe aperture 23, a lensing system is provided and it ismounted on the upper side of the division wall or partition I4 incentered relation to the aperture to receive the light rays reflectedfrom the globe surface. The system is made up of suitable lenses 41,preferably with a magnifying power of twenty (20) diameters, enclosedwithin a tube 48 oi proper dimensions, with its lower end secured aboutthe edge of the aperture 23 in a manner to prevent light leakage. Thechart-image to be projected by this lensing system is received on acircular translucent screen 49 that is fitted within the upper end ofthe upstanding flange. of the neck portion of the casing II. The screen4! may be of either the SA or the SB type and, while both areessentially the same, except that the SA type is concavo-convex and theSB type flat, the SA type is preferred for present purposes. The screen49, therefore, takes the form of a segment of a hollow sphere and, toaccord with the other dimensions given herein, has an arc length oftwenty (20) inches' I Encircling the flange l3, at the edge of thescreen 49, is a trackway 59 which, in turn, is encircled by an azimuthring 52, i. e., a circular ring, calibrated into 360 degrees andprovided with the cardinal direction points. The trackway 50 may takethe form of a circular ring secured aboutthe edge of the flange I3, witha channel in its upper side and an outwardly directed flange 5| uponwhich the azimuth ring 52 is mounted for circular turning motion.Mounted on the upper side of the screen 49, diametrically thereof, is atransparent plotting rule 53, twenty (20") inches in lengthand curved tothe same curvaturev as the screen, with its ends convexed to match thecurvature of the screen margin. The surface of the rule is calibratedinto correspond ing miles and has a center slit 54 extending lengthwiseto within one (1") inch of each end, where a straight line 55,constituting an index, extends outward to the rule end for cooperationwith the azimuth-ring. The opposite side edges ed the drift wind;Measnrementnoffitheudis tance to move the; rule in degrees is:-

of the rule 53' aregrooyed; as at 56; 'to receive lateral trolleys atthe ends of a slide-indicator Whichis preferably rectangular in form andmade-of a transparent material. The ends of the rule 53 arepivoted towheeled tro1leys'581, that are engaged-in the channel of the: trackway511;. for' its angular adjustment relatively to the screen margin. l l

The casing H is'formed of an opaquematerial and ismounted on a ring gear59, which, in'tu-rn,

ismounted for rotative motion on a circular base 50 "Risingfrom-the-base 50, spaced relation about" the casing, "are a series ofstrutstl which and has a. width topartially' overlie the flange 12,}substantially as 'shownl in FigureB. The base BI is provided with alateral offset 51 to gi-ve hearing to the lower end of a shaft: 64 whichcarries agear 65 arranged inmesh with the ringgear" 55; Likewise, :thecircular member" 52 is provided with anoffi'seti 56- having an aperturefor the projection of" the shaft B4-npwardly through. the same. theprojected shaft endhaving a "control knob 51' for itsmani-pulation". Alocking means (not shown) will be provided to secure the casing H in anyof its positions of angular adjustment relatively to the base- In.operation, with theinstrument' installed on an airplane, and beforedeparture, the illuminatingcsystem. 45 will be energizedand the globe/l5isrotated fromthe" control knobs 3'3, 43, to' place a given area of itssurface inregistry withthe aperture 23-, for the projection of thatarea, by the lensing system 41, onto-the screen-45.- The globe I5 isthen looked in its set position by pushingdownwardly on botl r of thedials33, 43, to mesh thepim'ons 3'0; 38; with the gears 29, 31.Following this, the chart-image on the screen 49 is oriented by aligningthe magnetic azimuth, projected by that portion of the globe surface,with a compass. This is accomplished by rotating the casing .l I,through the meshing gears 59, 55, from the operating dial 61, until therequired alignment is obtained, when the casing will be i locked in itsset position. With this setting of the casing, the azimuth ring 52 isturned about,

the flange 13 so that its north indication is in alignment with truenorth on the chart-image and it is then looked in set position.

With the instrument thus conditioned, the course, to be followed in theflight of the airplane, is plotted by, first, drawing a line, witherasable crayon, on the screen over the chartimage, from the point ofdeparture to and through the destination point to the outside margin ofthe screen. Here, the index 55 indicates a degree-mark on the azimuthring 52. Now, the plotting rule 53 is placed over the drawn line for itsregistry with the slit 54 and the slide-indicator 51 is thereafter movedto a position where its forward margin is in registry with the point ofdeparture. With the airplane in flight, the slideindicator 5! is movedalong the rule 53 correspondingly with the ground speed of the airplaneand, whenever drift occurs, the rule 53 is moved the proper number ofdegrees, its forward end with reference to the azimuth-ring 52, to theleft,

or right of the drawn line, as the case may be, and is moved back to itsoriginal position as the drift is corrected. If allowance is made forthe drift, the rule 53 is moved the number of degrees-of-allowance tothe left or right of the drawn line and thereafter is moved back towardsits original position as the airplane is shiftomltheazimuth ring scaleand the. pointbfdeparture on; flight is! alwaysrthe. point of? pivot; ofthe rule 5am its shifting movement for determining the angle of drift,or points llyingalong the flight course. 'I'he'position of theJairpIane,

in relation to the earthsesurface, is the point. in-

dicated by-the intersection ofthe' slit 54 in the ruleand the forwardmargin of "the-slide -indi-fl cator S IoVerthechaIt-image.'Iheprovi'sion of the elongated slit-54qinthe rule, makes possiblethedrawingoflines andangles, or the-marking o-f'pointsalon'g' the flightcourse; by'inserti'ng a crayon-pencil through it. The sides ofthe rule53 may, of course, be used as a straight-edgef'or to measure distances.5 a l Considering certain details of the invention, not previouslytouched'uporr herein, i-tisto be noted that the rollers- 24, 34, willpreferably be made of a material, such asrubberbrthel'ilce", which willafford efleotive frict ionai" contact of their peripheries with thesurface of the globe I5; in order that extreme accuracyin adjustment ofthe globe, with reference to the projection aperdrawing linesand themaking of calibrations used ture 23 behad. Also, that thelensing.,system to be employed has a double inversion 'effect; jso

that the. chart-image projected thereby ontoj the screen 48. will. he.erect. and all. points in. their proper positions. Thepurposeofconsideiringboth Wpesofscreens is thatl each, has its particularadvantage. With the curved screen, the SA. type, an exac-trepresentationof-.-the earthssurface can be projected onto it, since. the i-magetis.reflected from a. convexecurvedwsu-rface, i. e.,, the globe; l5,

and is received on. aconcavo-convex-curved screen as it appears on thesurface of the globe.

which. is concentric to the globe. In the case of the flat screen, theSB type, the projection is,

' will likewise be flat.

Having thus fully described our invention, it is to be understood thatvarious changes in design and in minor details of construction andarrangement of parts may be resorted to, without de- 9 parting from thespirit of the invention, or its scope as claimed.

What we claim is:

1. In a device of the class described, a casing having an opening, atranslucent projection screen closing the opening, a lensing systempositioned within the casing behind the screen and centered with.respect thereto, a globe having a map of the earth depicted on itssurface mounted for directional rotative movements within the casingbehind the lensing system, and means within the casing for illuminatinga given area of the globe surface for the reflection of a chart image ofthe illuminated area therefrom, to, and through, the lensing system andonto the screen. l

2. The device as in claim 1, with the casing mounted within a supportingframe and means carried by said frame for rotating said casing inrelation thereto for the orientation of the chart image projected ontothe screen with respect .to the magnetic azimuth, by means of a compass.

' 3. The device as in claim ,1, with mechanisms withinthe casing foreffecting directional rotation of the globe relative to thelensingsystem, and control means exteriorly of the casing for operating themechanisms.

4. The device as in claim 1, with a partition dividing the interior ofthe. casing into compartments, and having a projection aperturecenmargin of the projection screen, a degree scaled teredtherein, thelensing system being mounted on one side of the-partition at theaperture and thegglobe and the illuminating means therefor at theopposite side of said partition, said illuminating means being carriedby the partition about said aperture.

5. The device as in claim 1, with Y the projection screen of convexform, concentrically disposed with respect to the curvature of theglobe, the lensing system and said illuminating means, having an areasubstantially greater than the said screen, illuminated area of theglobe.

6. The device as in claim 1, with a degree scaled azimuth-ringrotatively mounted on the casing about the margin of the projectionscreen for turning movements to position its North indication [inalignment with the True North of the chart-image projected onto thescreen.

7. The device as in claim 1, with a transparent'plotting rule, scaledlongitudinally with mile graduations, mounted on the casing andextending'across the projection screen, the rule being angularlyadjustable relatively to margin of the screen for the plotting of flightdirection of an airplane on the screen, relatively to the chart imageprojected thereon. I

8. The device as in claim 1, with a trackway supported on the casingand'encircled about the azimuth ring also supported on the casing andencircled about thetrackway for turning movements about the same,relatively to the margin of the 9. In a device of the class described, acasing open at its upper end, a translucent projection screen closingthe opening, a globe having amap of the earth depicted on its surfacemounted for directional rotative movements within the cas: ing, meanswithin the casing for projecting a chart image of a given area of themap onto the screen, a trackway supported on the casing and encircledabout the margin of the screen, a degree scaled azimuth ring alsosupported ,on the casing and encircled about the trackway for turningmovements relatively to the margin of the screen, a trolley movable onthe trackway, a transparent plotting rule, scaled longitudinally withmile graduations, extended across the screen and having one end pivotedto the trolley for its angular adjustment relatively to-the margin ofthe screen and the azimuth ring, and an indicator slide mounted on therule relatively to the mile graduations thereon, the rule beinglongitudinally slitted at its center and between its ends for theinsertion therethrough of a crayon-pencil for the delineation on thescreen surface of the course of flight of an airplane.

ARTHUR R. MORLEY. f ROBERT c. MORLEY.

